Experimental validation of a human vertebra parametric model by comparison with real vertebra

The study of the behaviour of vertebral column of an individual requires the analysis of many elements which can be deduced from its vertebrae: the geometrical conformation, the kinematics, the material properties and the contacts between vertebra and vertebra. Moreover, the customization for each patient of a generic model, in terms of a complete dimensional characterization and the definition of anomalies, allows the prevention, the diagnosis, the detailed posture analysis and the evaluation of possible therapies. To this purpose, a parametric model of vertebra, capable of simulating each element constituting the vertebral column has been developed in the Department of Mechanical Engineering of University of Salerno, using a typical CAD software. This model allows the customization of cervical, thoracic, lumbar vertebrae and pelvis, for every individual. In order to evaluate the accuracy, the potentialities and the limits of the implemented model, a comparison among some real thoracic vertebrae and the correspondent reproductions in CAD system is presented. Six human vertebrae have been considered and analysed; the vertebrae have been selected from odd individuals from the necropolis of Geili-Sudan (4° cent. B.C. - 19° cent. A.D.). For each acquired vertebra, a set of parameters has been calculated; this set has been applied to parametric model to obtain CAD representation, and the morphological and dimensional correspondences have been evaluated.